Summary for clan MD

Clan type peptidase	M15.001 - zinc D-Ala-D-Ala carboxypeptidase (Streptomyces-type) (Streptomyces albus), MEROPS Accession MER0001357 (peptidase unit: 116-255); PDB accession 1LBU
History	PEPTIDAS.TXT (SwissProt document)
Description	Water nucleophile; water bound by single zinc ion ligated to His, Asp and His
Contents of clan	Clan MD contains peptidases that are involved in bacterial cell wall biosynthesis and lysis.
Evidence	The homology of families M15 and M74 is shown by similarities in the protein folds of zinc D-Ala-D-Ala carboxypeptidase (M15.001) and murein endopeptidase (M74.001).
Catalytic mechanism	The metal ligands occur in the motifs His-Xaa(6)-Asp and His-Xaa-His, which are characteristic of clan MD.
Peptidase activity	Types of peptidase activity include carboxypeptidase (subfamilies ##M15A##, ##M15B##), dipeptidase (##M15D##), and endopeptidase (##M15C##, M74).
Protein fold	Tertiary structures have been determined for members of families M15 (Bussiere et al., 1998) and M74 (Marcyjaniak et al., 2004). Peptidases in clan MD are alpha/beta proteins with a bundle of helices and a four strand beta sheet. Two of the zinc ligands are on the beta sheet.
Homologous non-peptidase families	The N-terminal effector domain of hedgehog protein has a similar fold (Hall et al., 1995).
Other databases	SCOP	55166

Families

Family	Family Type Peptidase	Structure
M15	zinc D-Ala-D-Ala carboxypeptidase ({Streptomyces}-type) (Streptomyces albus)	Yes
M74	murein endopeptidase (Escherichia coli)	Yes